Barge with liquid level control system



May 30, 1967 A. .1. TUCKER 3,322,087

BARGE WITH LIQUID LEVEL CONTROL SYSTEM Filed April 21, 1966 3Sheets-Sheet l AuyuJf/ne (I Tue/re,

INVENTOR.

y 1967 A. J. TUCKER 3,322,087

BARGE WITH LIQUID LEVEL CONTROL SYSTEM Filed April 21, 1966 3Sheets-Sheet. 2

65 4 914: f/n e (I Tackefi v INVENTOR.

BY //4I?R IS nun L44 Km! y 1967 A. J. TUCKER 3,322,087

BARGE WITH LIQUID LEVEL CONTROL SYSTEM Filed April 21, 1966 3Sheets-Sheet.

65 INVENTOR.

A @114 f/n e z/T Tucker BY 4/?R I5 41w 14R KIN United States Patent3,322,087 BARGE WITH LIQUID LEVEL CONTROL SYSTEM Augustine John Tucker,911 S. Post ()ak Laue, Houston, Tex. 77027 Filed Apr. 21, 1966, Ser. No.544,157 Claims. (Cl. 114-.5)

This invention relates to a barge with a liquid level control system foraccumulating and storing a water immiscible liquid having a specificgravity less than water at a substantially constant hull displacement.More specifically, this invention relates to a semi-submersible tankbarge with a liquid level control system for accumulating, storing andtransporting a water immiscible liquid such as oil from an oflshorelocation to a shore location. The "barge of this invention isparticularly adapted for mooring in the open sea, with the controlsystem functioning to load the oil thereinto with a minimum of attentionand care, since it will float at a substantially constant level ofsubmergence, i.e., within predetermined limits.

In the conventional production of oil at oflshore locations, it iscustomary to have fixed tanks mounted on the production platform whichhave sufiicient capacity so that when an empty oil barge is brought inby a tug, the barge can be loaded and dispatched to the terminal asquickly as possible. Hence, there is a problem of providing a space forthe fixed tanks, as well as the necessity for transferring the oil fromthe tanks to the barges at the desired times, which times may be limitedby Weather or wave action. I

In contrast, the barge of this invention is designed to be moored inposition near the points of production for long periods of time, withthe oil production being di-' verted directly to the barge as itaccumulates, which will be at a relatively slow rate. The barge must beable to withstand wide variations in weather and wave action and tocontinue to act as an accumulation and storage vessel or barge, evenduring times of critical weather.

The barge of this invention not only reduces the time and expenserequired for accumulating and storing the oil, but provides a safermeans for handling the oil. The design of the barge is such that,because it is submerged, it receives sea action thereagainst almostentirely from the intensity and direction of the current flow. The bargeis so configured that it can take the current action on either endwithout yawing. It is also adapted for mooring in such a fixed positionthat the loading connections will be held close to a fixed point.

Prior art hulls have been designed to float at deep submergence.However, in almost every instance they a e either manned stations suchas a floating drill rig platform, or they are unmanned stations, likeweather buoys which have no variation in on-board weight. In neitherinstance is wind loading avoided, nor are they designed specifically tohave their moorings laying entirely to the set and drift of the current.

It is therefore, an object of this invention to provide an improved andnovel semi-submersible tank barge with liquid level control means, whichbarge is adapted for mooring in the open sea adjacent to a producingwell for the purpose of accumulating, storing and subsequentlytransporting the oil to a shore terminal, which barge overcomes theforegoing short-comings of the prior art and provides a solution to theproblems mentioned above.

Briefly stated, the barge of this invention includes a first tank orcargo tank adapted to be initially filled with water and substantiallysubmerged, and having outlet means near the bottom thereof and inletmeans near the top thereof. A second tank or buoyancy tank is attachedto and supported above the first tank and is adapted to 3,322,087Patented May 30, 1967 be initially substantially empty of any liquid. Athird tank or reserve tank is attached to at least one of the said firstand second tanks and extends above the water line in which the barge isfloating for providing the barge with reserve buoyancy to .preventcomplete floundering or submergence of the barge.

There is also provided independently floating receiver means which areassociated with the first and second tanks for receiving the liquidwhich is to be stored and accumulated in the barge. Valve and conduitmeans are provided for interconnecting the receiver means and the firstand second tanks for flowing the liquid from the receiver means into thefirst tank initially to displace water therefrom, and to alternatelydivert the liquid to the second tank when the first tank rises apredetermined distance relative to the receiver means as said liquiddisplaces the water from the first tank.

Reference to the drawings will further explain the in-- vention wherein:

FIG. 1 is a perspective view of a barge made according to the presentinvention, showing it moored in an open sea position adjacent toproducing oil wells.

FIG. 2 is a cross-sectional view through the center of the barge shownin FIG. 1 and showing the barge partially loaded or filled with oil.

FIG. 3 is a view similar to FIG. 2 but showing the barge substantiallyloaded with oil.

FIG. 4 is a fragmentary and enlarged view of the oil receiver of thebarge shown in FIGS. 2 and 3.

FIG. 5 is a schematic end elevation view of an alternate embodiment ofthe invention.

Referring now to FIG. 1, the barge of the present invention is generallyshown by the numeral 11 and is provided with a pair of elongatedcylindrical cargo tanks 12 which are connected to and supported byelongated dome shaped buoyancy tank 13 which has connected thereto andsupported therea'bove, three tubular shaped tanks 14 which providereserve buoyancy to the barge to prevent complete submergence of thebarge and are selected to be of a size sufiicient to support at leastthe weight of the materials comprising the barge structure. For purposesof convenience, tanks 14 may sometimes be referred to eithercollectively or individually as a reserve buoyancy tank, and there maybe one or more such tanks.

The barge is moored to the set of the current by means of anchors 17connected to the barge by anchor lines 18 of conventional design. Thesource of the liquid which is to be stored in the barge 11 is fromproducing oil wells 20 which are connected to collecting conduits 21which in turn are connected to flexible hose 22 which leads to thereceiver means provided in center tank 14.

With the barge in position as shown in FIG. 1, its principal bulk issubmerged well below the surface of the water. The three cylindricaltubes or tanks 14 pierce the wave zone, extending above it enough toprovide a reserve buoyancy and to provide an above water level forperforming handling operations on the barge. It is to be understood thatdome tank 13 also provides buoyancy and is mounted on top of cargo tanks12 such that the center of buoyancy of the barge is always above thecenter of gravity of the barge.

With the hull floating in the position shown in FIG. 1 and having thestructure shown, the barge receives practically no loading from windsand there is very little wave action against the tanks 14. While therewill be some action from deep wave forces against the faired surfaces ofthe hull, including cargo tanks 12, it is to be understood that in thedeep submerged condition shown, any forces against the barge will bealmost entirely caused by current flow. Since estuarial tidal currentsare usually directly reversible between ebb and flow and since most opensea currents are persistently in one direction, it is possible to anchorthe barge in a fixed position relative to said currents whereby wave andcurrent action will be at a very minimum. So positioned, the bargereceives any sea action thereagainst almost entirely from the intensityand the direction of current flow and it is so configured and shapedthat it can take this loading on either end without yawing. Thus, it canbe moored such that its cargo loading connections will be held close toa fixed point. It is possible, of course, to moor it at one end only sothat it will be free to orient to variable current flows. The principaladjustment which would be required would be to revise the loading hoseconnection so that it will accept the full circumferential swing of theuniversal mooring.

In prior art submersible barges, various means have Q been employed tokeep the hull from rising. For example,

water ballast has been used by pumping it into tanks placed above thewater line. Alternatively, heavy weights have been suspended from thebottom of the hull so that they will rest on the sea floor while thehull is in a submerged condition, bringing their load into effect as therising hull picks them off the bottom. However, the for' mer instancerequires human attention and expensive addition of facilities. Thelatter is crude in its adjustment feature and requires an equivalentextra facility cost. The control features of the present inventionprovides a solution to this problem and will now be explained byreference to FIG. 2. Tan-k 14, which may be open at its upper end, isattached to and supports dome tank 13 at its lower end. Tank 14 and dometank 13 have passing downwardly therethrough a vertically extendingelongated tube 25 forming an open ended column therethrough.

Dome tank 13 is provided with a plurality of partitions or bulkheads 26which'extend longitudinally thereof. It is to be understood that similarpartitions or bulkheads could also be provided transversely thereof.Each of the partitions or bulkheads 26 is provided with valve 27 whichcan be remotely operated (by means not shown) for evacuating oiltherefrom at the terminal location. In addition, the bottom portion ofdome tank 13 is provided with outlet valve 28, which is also used forunloading purposes. Tank 13 is also provided with inlet means near thetop thereof in the form of fixed conduits 29 which lead upwardlytherefrom as shown. 1 Dome tank 13 has attached thereto and supportseach of the cargo tanks 12. Each of the cargo tanks 12 has inlet meansin the upper portion thereof in the form of openings 30, each of whichconnects with or communicates with a conduit tube 31 which lead upwardlytherefrom, as

shown.

Each of the tanks 12 has outlet means in the lower por 'tion thereof inthe form of outlet conduits 33 which lead to the column inside of tube25. Each of the conduits 33 is controlled by valve means which includesa valve 34 which may be remotely operated (by means not shown).

Tube 25 has mounted therein for independent floating therein cylindricalfloat 38 which is adapted to float in r the column of water or a liquidstanding in tube 25. Float 38 has connected thereto and supportsthereabove receiver means for receiving oil from flexible hose 22, whichreceiver means includes elbow joint 41 which is connected to deposit oilinto cylindrical container 42, the bottom end of which is connected to avertically extending shank 43 which fits inside of and is adapted fortelescopic movement with respect to tubular member 44, the lower end ofwhich is connected, as by welding, to float 38.

Tubular member 44 has a plurality of vertically spaced pairs of holes 47which are adapted for passage therethrough of bolt 48 which similarlypasses through shank 43. Thus, the height at which container 42 issupported relative to float 38 can be adjusted by removing bolt '48 fromone of the pairs of holes 47 and repositioning means in the form of apair of lower openings 50 and portions of cargo tanks 12. Conduits 54are provided with sufficient slack so that there may be relativevertical movement between container 42 and conduits 31. 1 a

Similarly, upper openings 51 connect with flexible conduits 55, thelower ends of which connect with the upper ends of fixed conduits 29.Again, conduits 55 are provided with slack so as to provide for relativevertical movement between container 42 and conduits 29.

Referring now to FIG. 4, container 42 alsohas floating therein floatvalve 58 which is slightlysmaller in diameter than the inside diameterof container 42.' Valve 58 is provided with a central valve plug 59which is adapted to close with the lower end of elbow joint 41 andthereby shut off the flow of liquid or oil therethrough. Valve 58 alsohas passing therethrough a plurality of vertically extending openings 60which permit the flow of oil there-v through when plug 59 is not in aclosed position, as shown in FIG. 4. Valve 58 will be forced or liftedto the closed position only when the liquid level in container 42 risesReferring now to FIG. 2, float 38 has attached to the lower end thereof,as by welding, valve means which includes valve rod 62 which dependsdownwardly therefrom. Rod 62 has attached to the lower end thereof acylindrical sleeve member'63 having horizontally extending valve ports64 which are adapted to mate with the open ends of conduits 33 when inthe position shown in FIG. 2. In addition, sleeve 63 is provided withgenerally vertically extending openings 65 which provide communicationto the column inside of tube 25.

Rod 62 also has supported near the lowerend thereof centering guidemeans in the form of spider 66"which is adapted for relative verticalmovement up and down in- 'side of tube 25 coincidentally-with themovement of rod 62 and float 38. V

In operation of the barge shown in FIGS. 1, 2 and 3, it will beinitially placed in the position shown inFIG. 1, i.e., it will bepartially submerged with only tanks 14 ex- .tending above the watersurface. Cargo tanks 12 will be substantially filled with water if notcompletely filled with water and dome tank 13 will besubstantially'empt-y of oil is flowed through. flexible hose 22 to elbowjoint 41,.

which provides'the inlet means to container 42.

The principle whereby the oiliis then flowed to cargo tanks 12 is basedon U-tube balance; Depending upon the specific gravity of the oil orliquid'bein-g collected or to be collected in tanks 12, container 42 isadjusted or set the desired distance above float 38 by adjustment ofbolt 38 with respect to pairs of holes 47, such that the oil collectedin container 42 will automatically-flow into and displace water fromtanks 12,'as willnow be explained.

When oil collects in container 42 and rises to liquid level 68 the oilwill flow out of lower openings 50 into'flexible conduits 54, to conduittubes 31 and into the upper .portions of tanks 12. As oil is flowed intothe upper portions of tanks 12,.water is displaced from the lowerportions thereof and out conduits 33 throuigh valve ports 64. Thisdisplacement of water. in the manner described occurs because ofthe'U-tube principle. In other words, the weight of the column of oiland water in conduits 54 and 31 and to the bottom of tanks 12 issuflicient to overcomej the head pressure of the water column at thebottom of tanks 12. Hence, water is displaced from tanks 12 by what maybe described as gravity flow, based on the U-tube principle.

As oil continues to accumulate in tanks 12 by the aforesaid gravity flowbased on U-tube principle, tanks 12 will thereby gain buoyancy or becomelighter to the extent that theoil has a lower specific gravity than thewater which is being displaced. As this occurs, tanks 12 will tend torise vertically relative to float 38. As this occurs, the barge willassume the position shown in FIG. 3. As tanks 12 rise relative to float38, sleeve member 63 and hence valve ports 64 are caused to movedownwardly relative to the open ends of conduits 33 such that outflowthrough conduits 33 is stopped. This results in the accumulation of oilin container 42. As oil accumulates in container 42, it rises to thepoint that oil flows out openings 51 through flexible conduits 55 toconduits 29 and thence to the upper portion of dome tank 13. Bulkheads26 in tank 13 insure that oil first accumulates near the center thereofto prevent tipping of tank 13. As oil accumulates behind each of thebulkheads 26, and fills up the space therebehind, it then spills over toan adjacent spacing provided by an adjacent bulkhead 26 such that dometank 13 is loaded from a center point outwardly, thereby insuringstability of dome tank 13.

As the oil accumulates in tanks 12, the on-board weight changes sincethe heavier sea water has been replaced with lighter oil. The hulladapts to this weight change by risinthis being the only way that it canreduce its total displacement volume of the water. By having theoil-water leg floating, which is accomplished by float 38 which supportscontainer 42, the dimension of the oil and water leg of the U-tube willbe fixed, while the water leg of the U-tube changes when tanks 12 moveup and down.

With the control feature, i.e., the oil-water leg, at constantdimension, then the motion of the barge upward can be used to switch theloading of the oil from tanks 12 to tank 13.

The cause for the rising of the barge, including tanks 12, may bedefined as caused by diminishing displacement due to reduced totalweight, Another interpretation would be that the barge has becomeover-buoyant. The switch of the oil loading from cargo tanks 12 tobuoyancy tank 13 may be described as a cancellation of theover-buoyancy. Since tank 13 is initially substantially empty of anyliquid, it is ready to accept or accumulate oil therein.

As oil is accumulated in tank 13, the buoyancy thereof is reduced to theextent that oil is accumulated therein. This accumulation causes thebarge to sink downwardly relative to float 38 because of loss ofbuoyancy. As tanks 12, 13 and 14 move downwardly relative to float 38,valve ports 64 become once again aligned with the open ends of conduits33 such that outflow from tanks 12 can start again. When tanks 12 havetaken on suflicient oil to cause the barge to rise again as describedabove, the cycle can be repeated. Hence, it may be stated that theconduit and valve means are arranged such that oil is alternatelydiverted from tank 12 to tank 13 until the loading is completed.

When tanks 12 and 13 become fully loaded with oil, then oil willaccumulate in container 42 and rise above upper openings 51 so thateventually valve plug 59 will close off inflow of oil to container 42 asshown in FIG. 4. It is important that container 42 be supported asuflicient distance above float 38 such that the weight of the oilwatercolumn of the U-tube will not be so great as to cause underflow oroutflow of oil through conduits 33.

In conduit 54, an oil level will exist so that the combined oil-waterweight on the tank side will overcome water head on outflow side.Eventually, when all water is purged through conduit 33 to sea, the oilonly column in tank 12 andconduit 54 will stand at a point ready to exitout conduits 33, provided container 42 is adjusted to proper height forthe three variables-the specific gravity of the immersion fluid, thespecific gravity of the oil, the depth of water to the bottom of tank12.

When oil is loaded onto the barge by introduction into the top ofcontainer 42, it will flow into conduit 54. At the start of loading,when the water level in tanks 12 and conduits 54 is the same as theexterior water level, the addition of the oil on top will cause anunbalance in the U-tube and water will flow out through conduits 33,valves 34 and ports 64. As the oil level extends downward in tank 12,the oil level in conduits 54 will also be rising, so that the weight ofthe combined oil-water column will always be greater than the weight ofthe column of only water on the outside. The level of oil at the heightof openings 51 in container 42 must be set so that when tanks 12 arecompletely filled with oil to the level of conduits 33, the height ofthe column up to the level of openings 51 will be equal in weight to theweight of the column of water exterior to the tank. Thus, there arethree variables to be met in the adjustment, i.e., the specific gravityof the oil being loaded, the specific gravity of the water in which thetank is floating, and the depth the outflow point below the water line.

Hence, the adjustment feature of bolt 38 relative to shank 43 and tube44 is provided so that precise balance and control will exist in thetermination phase of the loading of the tanks.

In order to determine the precise distance which container 42 must besupported above the water line, it is necessary to determine therequired height of the oilwater leg in order to displace water fromtanks 12. The formula by which this can be computed is as follows:

Specific gravity of the water of hull This calculation will give theexact height of the oilwater leg. To get the setting of the adjustmentabove the Waterline on float 38, subtract the designed draft of tanks12. In addition to adjusting bolt 48, weights may be supported on float38 in container 42 such that container 42 is supported at the desiredheight to accomplish the correct weight in the oil-water leg asdescribed above. 7 Since container 42 will contain a variable amount ofoil during the operation of the barge, the specific height at whichcontainer 42 must be set must take into consideration the dynamicconditions that will prevail. There will be a quantity of oil incontainer 42, the weight of which will vary as the level therein risesand falls during the loading operation. Hence, a final setting of theheight of receiver 42 is selected to take into account these dynamicconditions. As noted above, this final setting can be made by adjustingthe height of container 42 relative to float 38 and/or by adding weightsto or removing weights from float 38.

When the barge is loaded, i.e., when tanks 12 are filled, and/ or whentank 13 is filled, if this should occur prior to the filling of tanks12, then the barge can be disconnected from flexible hose 22 and toweddirectly to the terminal without the need to transfer to another tankbarge, thereby eliminating one handling operation entirely. During themovement of the barge of this invention to the terminal or unloadingpoint, there are also many advantages of this barge over other 'barges.It can be towed in a submerged condition. Since it is riding generallybelow the wave zone, the barge will not incur impaction from the waves,which ordinarily reduces speed. At the unloading terminal, the dome tank13 would be unloaded first as by opening valve 28 and pumping the oiltherefrom. Thereafter, tanks 12 can be unloaded either by closing offvalves 34 and then pumping the oil therefrom in a conventional manner.Alternately, cargo tanks 12 can 'be unloaded by ingesting waterthereinto. This will create a positive pressure on the suction side ofthe cargo pumps, assisting in the efiiciency of pumping.

There are many other advantages of this barge and liquid control system.For example, in a conventional barge, when all of the valves to all ofthe tanks are open and loading commences, there will be a low end or alow specific gravities,

' proportional for a series could be attached to float '38 or placed onreceiver 42.

side. Because the piping is sloped in the direction of the low point,that tank will gradually move ahead of its companion tanks andaccumulate oil faster. This tends to exaggerate the trim condition. Ifhuman supervision :is not present to operate valves to bring the tanksup evenly, the low point tanks will overflow before the high point tanksreach full capacity.

By contrast, with the water displacement system of this invention, theopposite eflect is found to be the case. If a low tank is receiving oilat a faster rate than the others, it will become lighter instead ofheavier. Thus, there is a built-in tendency to restore the slope of thepiping back to the horizontal position and there-by remedy the cause ofthe extra flow into the one tank.

Another advantage of the instant invention is that by having the oilflow to dome tank 13 to be initially to the central part thereof, dometank 13 will be loaded uniformly. Hence, bulkheads 26 in dome tank 13prevent the creation of a low side during loading thereof.

These two features of trim control permit this barge to be loadedwithout human attention.

Another advantage of the embodiment shown in FIGS. 1, 2 and 3, is thatthe oil-water leg of the U-tube principle, i.e., float 38 and container42, are enclosed within 7 tube 25. Hence, the control system is shieldedfrom the turbulence of the wave zone. Float 38 is not free from rise andfall caused by wave passage on the outside of the barge; the changes inhydrostatic head will be reflected in surges within the'column. However,all of the elements in this system are also enclosed in the column,i.e., both the oil-water leg of the U-tube, and the outflow openings intanks 12. Hence, operating conditions will remain substantiallyuneffected by wave action. When float 38 rises on top of a surge, thecause of the rise also causes a counterbalance in the U-tube or thewater-leg of the U-tube.

.There is also a built-in safety factor in the design shown in FIGS. 1,2 and 3, in that the outflow from conduits 33 is to the column inside oftube 25. If it should occur that oil should escape from tanks 12 outconduits 33, the oil will rise to the top of the water in the columninside tube 25. As the oil in the column inside tube 25 accumulates,float 38 will adjust its displacement to suit the lighter medium inwhich it is then floating. Float 38 will thereafter sink deeper andeventually close the outlets from conduits 33. This will prevent the oilfrom migrating outward to the sea, thus preventing contamination andfinancial loss. a

To assure that precise control can be maintained across the full rangeof different kinds of oils having ditfer'ent 'the dimensions of thebarge and its various elements and control system can be designed for aheavyweight oil, as for example, 20 API. By establishing such a basepoint for the receiver design capacity, standard float and valvedimensions would follow accordingly. For oils of less specific gravity,lead weights of different specific gravities Referring now to FIG. 5,another embodiment of a barge incorporating the invention is shown. Asexplained a above, FIG. shows a schematic view of a barge having cargotank 71 with outlet means in the lower part thereof in the form ofconduit 72 and inlet means in the upper portion thereof in the form ofopening 73. Tank 71 has attached thereto and supports thereabove domeshaped buoyancy tank 75 which also has attached to the upper end thereofa third tank 76 which acts as the reserve buoyancy tank and extendsabove the water line. Tank 76 is also cylindrical in shape with the topend closed and isadapted for fitting inside of and for vertical relativemovement with receiver valve sleeve 78, thereby forming a receivingchamber thereabove, for receiving oil thereinto. Sleeve 78- has loweroutlet means which communicates with flexible conduit 79 which connectswith inlet 73 of tank 71. Similarly, sleeve 78 has upper outlet meansWhichcommunicates with flexible conduit 80 which communicates with thetop portion of tank 75.

Tank can be provided with bulkheads similar to bulkheads 26 shown in theembodiments of FIGS. 2 and 3, if desired. Oil is supplied to the insideof sleeve 78 through flexible hose 84 which corresponds with hose 22 inFIG. 1. Hose 84 is connected to a rigid flow line 85 which attaches atone end to sleeve 78 in a fixed relationship and at the other end to arigid float connector 86 also in a fixed and rigid relationship. Floatconnector 86 is rigidly connected to float 87 which corresponds withfloat 38 of the embodiment of the invention shown in FIGS. 2 and 3.However, in this instance float 87 is not isolated from the wave actionto the extent that float 38 is, and for that reason the control featureof this embodiment would be less precise. Nevertheless, the operationalfeatures are'essentially. the

same as with the embodiment shown in FIGS. 2 and 3,

from in the same manner of operation as with respect to the embodimentshown in FIGS. 2 and 3. In other words, the height at which sleeve 78rides above the waterline is selected such that the Weight of the oiland water col-' umn of the U-tube principle is suflicient to overcomethe weight of the water column of the -U-tube principle. This height ofsleeve 78 is determined by its relation-ship to float 87 since it isrigidly connected thereto. Thus, means can be provided (not shown)whereby float connector 86 may be elongated or shortened and/ oradditional weight added to or removed from float 87such that sleeve 78may be supported the desired distan ce'a-bove the water line in the samemanner that container 42 was supported above the water line as shown inFIGS. 2 and 3.

As oil accumulates in tank 71 and water is displaced therefrom, thevessel will tend to rise thereby forcing tank 76 upward where it acts asa piston. As tank 76 moves above the lower outlet of sleeve 78, oilwillaccumulatev therein until it flows through conduit 'to tank 75. Astank 75 is loaded, the barge will sink to the point that oil once againflows through conduit 79 to tank 71. This alternating flow of oil totanks71 and 75 will continue until the loading operation is complete inthe same manner as with the embodiment shown in FIGS. 2 andg3. In

other words, it may be stated that tank 76 acts as a sleeve valve.

Nevertheless, the control system of FIG. 5 is similar to that shown inthe embodiment in FIGSVZ and '3. Rather than controlling the outflowfrom-tank 71, as does the embodiment of FIGS. 2 and 3, the inflowthereto is controlled by the embodiment shown in FIG. 5.'Nevertheless,the'valving action is still responsive to the vertical movement of tank71 during the loading thereof. Thus,

it may be stated that both of the embodiments have valve means which areresponsive to the vertical movement .of the cargo tank for alternatelydirecting oil between the cargo tank and the buoyancy tank. In bothinstances, the

. receiver means is mounted to float independently of the cargo tanksand buoyancy tank. In both of the embodiments there are conduitmeansfconnecting the receiver means with both the cargo tank and thebuoyancy tank.

Similarly, the embodiment shown in FIG. 5 also has the advantage ofbeing substantially submerged and, therefore, removed from wave action.It can be easily moored in the open seal position and moved to aterminal loca-' tion with a minimum of wave action thereon.

Further modifications may be made in'the invention as described withoutdeparting from the scope of the invention. Accordingly, the foregoingdescription is to be construed as illustratively only and is not to .beconstrued as a'limitation upon the invention as defined in the followingclaims.

What is claimed is:

1. A barge with a liquid level control for accumulating and storing awater immiscible liquid having a specific gravity less than Water,comprising in combination:

a first tank adapted to be initially filled with water and substantiallysubmerged and having outlet means near the bottom thereof and inletmeans near the top thereof;

a second tank attached to and supported above said first tank andadapted to be initially substantially empty of any liquid;

a third tank attached to at least one of said first and second tanks andextending above the water line for providing said barge with reservebuoyancy to prevent complete submergence of said third tank;

independently floating receiver means associated with said first andsecond tanks for receiving said liquid;

and, conduit means interconnecting said reeciver means and said firstand second tanks for flowing said liquid from said receiver means intosaid first tank initially to displace water therefrom, and toalternately divert said liquid to said second tank when said first tankrises a predetermined distance relative to said receiver means as saidliquid displaces said Water from said first tank.

2. The barge as claimed in claim 1 wherein:

said receiver means includes a liquid container mounted to floatindependently of said first and second tanks;

said conduit means includes a first conduit interconmeeting saidcontainer and said first tank and a second conduit interconnecting saidcontainer and said second tank;

and, including valve means responsive to the vertical movement of saidfirst tank for alternately directing fluid through said first and secondconduits.

3. The barge as claimed in claim 1 wherein:

said receiver means includes a liquid container mounted to floatindependently of said first tank within predetermined limits above thewater level in which the barge is partially submerged and having upperand lower outlets;

said conduit means includes a first conduit interconnecting said loweroutlet of said liquid container and said inlet of said first tank and asecond conduit interconnecting said upper outlet of said liquidcontainer and said second tank;

and, including valve means responsive to the vertical movement of saidfirst tank with respect to said liquid container for alternatelydiverting said liquid to said second tank as said first tank rises abovea predetermined level as said liquid displaces water therefrom.

4. The barge as claimed in claim 1 wherein:

the center of buoyancy of said barge is above the center of gravity ofsaid barge.

5. The barge as claimed in claim 1 wherein:

the buoyancy capacity of said third tank is suflicient to support atleast the weight of materials comprising the structure of the barge.

6. The barge as claimed in claim 1 wherein:

said receiver means is adapted to float above the water line a distancesuch that the head pressure of the column of liquid inthe conduit meansleading from the receiver to the first tank is greater than the head 1Opressure of the water to be displaced from said first tank.

7. The barge as claimed in claim 1 including:

an open ended column member extending vertically through the barge andforming a shaft therethroug-h, the lower end of which is incommunication with the water in which the barge is floating;

said receiver means includes float means which are adapted to float insaid shaft;

. and, valve means connected to said float means for closing ofl theoutlet means of the first tank when said first tank rises apredetermined distance, to thereby divert said liquid to said secondtank.

8. A semi-submerged barge having a liquid control system foraccumulating and storing oil, comprising in combination:

a cargo tank having inlet means near the top thereof and outlet meansnear the bottom thereof and adapted to be initially filled with waterand sub stantially submerged;

a buoyancy tank having inlet means and connected to and supported abovesaid cargo tank and adapted to at least initially provide buoyancy tosaid cargo tank;

a reserve tank connected to said buoyancy tank and extending above thewater line for providing said barge with reserve buoyancy to preventcomplete submergence of said reserve tank;

float means adapted to float independently of said cargo tank;

receiver means connected to and supported by said float means forreceiving oil deposited therein; first conduit means interconnectingsaid receiver means and said inlet of said cage tank; second conduitmeans interconnecting said receiver and said inlet of said buoyancytank; and, means for gravity flowing oil from said receiver through saidfirst conduit means to the inlet means of said cargo tank for forcingwater therein out said outlet means, and to alternate gravity flow saidoil through said second conduit means to said inlet of said buoyancytank when said cargo tank rises relative to said receiver apredetermined distance as water is displaced from said cargo tank. 9.The barge as claimed in claim 8 wherein: said receiver means includes acontainer having; inlet means for receiving oil thereinto, upper outletmeans connected to said first conduit means for discharging oiltherefrom, and lower outlet means connected to said second conduit meansfor discharging oil therefrom; and, said valve means includes means forflowing said oil out the lower outlet of said container initially andalternately flowing said oil out the upper outlet of said container assaid cargo tank rises as oil is collected therein. 10. The barge asclaimed in claim 9 including: second valve means adapted for closing offflow of oil to said container when the oil level therein rises apredetermined distance above said upper outlet.

No references cited.

MILTON BUCHLER, Primary Examiner. T. M. BLIX, Assistant Examiner.

1. A BARGE WITH A LIQUID LEVEL CONTROL FOR ACCUMULATING AND STORING AWATER IMMISCIBLE LIQUID HAVING A SPECIFIC GRAVITY LESS THAN WATER,COMPRISING IN COMBINATION: A FIRST TANK ADAPTED TO BE INITIALLY FILLEDWITH WATER AND SUBSTANTIALLY SUBMERGED AND HAVING OUTLET MEANS NEAR THEBOTTOM THEREOF AND INLET MEANS NEAR THE TOP THEREOF; A SECOND TANKATTACHED TO AND SUPPORTED ABOVE SAID FIRST TANK AND ADAPTED TO BEINITIALLY SUBSTANTIALLY EMPTY OF ANY LIQUID; A THIRD TANK ATTACHED TO ATLEAST ONE OF SAID FIRST AND SECOND TANKS AND EXTENDING ABOVE THE WATERLINE FOR PROVIDING SAID BARGE WITH RESERVE BUOYANCY TO PRE-